"It isn't necessary.

I understand the situation, now, and you shall never regret that you met Caleb Sweetwater on your walk this evening.

Will you trust me, sir?
A detective who loves his profession is no gabbler.

Your secret is as safe with me as if you had buried it in the grave." And I had said nothing! He started to go, then he stopped suddenly and observed, with one of his wise smiles: "I once spent several minutes in Miss Carmel Cumberland's room, and I saw a cabinet there which I found it very hard to understand.

But its meaning came to me later.